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Abstract:

Disclosed is a styrene-based resin composition that comprises 5-20 parts
by mass of (D) a fire retardant per 100 parts by mass of a resin
composition (1) that comprises 30-51 mass % of (A) a graft copolymer
obtained by graft polymerization of a diene rubber polymer with an
aromatic vinyl monomer and an unsaturated nitrile monomer, 10-55 mass %
of (B) a copolymer comprising two or more monomers selected from among
aromatic vinyl monomers, unsaturated nitrile monomers and unsaturated
carboxylic acid alkyl ester monomers, and 15 to 39% by mass of a
copolymer (C) comprising one kind of unsaturated carboxylic acid alkyl
ester monomers, or two or more unsaturated carboxylic acid alkyl ester
monomers, ((A)+(B)+(C)=100 mass %), wherein the diene rubber polymer
constitutes 15-25 mass % of the resin composition (1).

Claims:

1. A styrene-based resin composition comprising a resin composition (1)
and 5 to 20 parts by mass of flame retardant (D) based on 100 parts by
mass of the resin composition (1), wherein the resin composition (1)
comprising 30 to 51% by mass of a graft copolymer (A) obtained by graft
polymerizing a diene-based rubbery polymer with an aromatic vinyl-based
monomer and an unsaturated nitrile monomer, 10 to 55% by mass of a
copolymer (B) comprising two or more of monomers selecting from the group
consisting of aromatic vinyl-based monomers, unsaturated nitrile
monomers, and unsaturated carboxylic acid alkyl ester monomers, and 15 to
39% by mass of a copolymer (C) comprising one kind of unsaturated
carboxylic acid alkyl ester monomers, or two or more unsaturated
carboxylic acid alkyl ester monomers (wherein (A)+(B)+(C)=100% by mass),
and wherein a proportion of the diene-based rubbery polymer to the resin
composition (1) is 15 to 25% by mass.

2. The styrene-based resin composition according to claim 1, wherein a
falling dart impact-50% destruction energy according to JIS K7211-1976 of
a molded product comprising said styrene-based resin composition and
having a thickness of 2.5 mm is 4.0 J or more.

3. The styrene-based resin composition according to claim 1 or 2, wherein
a proportion of a unit component derived from the aromatic vinyl-based
monomer (As) in the components of the graft copolymer (A) from which the
diene-based rubbery polymer components are excluded is 60 to 90% by mass,
a proportion of a unit component derived from the aromatic vinyl-based
monomer (Bs) in the copolymer (B) is 60 to 90% by mass, and a difference
(|As-Bs|) between the proportion of the unit component derived from the
aromatic vinyl-based monomer (As) and the proportion of the unit
component derived from the aromatic vinyl-based monomer (Bs) is 0 to 5%
by mass.

4. The styrene-based resin composition according to claim 1, wherein the
component (C) is a copolymer obtained by copolymerizing a methyl
methacrylate monomer and a methyl acrylate monomer.

5. The styrene-based resin composition according to claim 4, wherein a
proportion of the methyl acrylate monomer contained in the copolymer (C)
is 0.5 to 15% by mass.

6. The styrene-based resin composition according to claim 1, wherein the
resin composition (1) comprises 1 to 12% by mass of an aromatic
polycarbonate (E), wherein (A)+(B)+(C)+(E)=100% by mass.

[0002] Conventionally, flame retardant styrene-based resins have
fabricability, a good balance of mechanical properties, and excellent
electric insulation, and therefore they are used in wider fields such as
electrical and electronic equipment and OA equipment. On the other hand,
recently, a trend toward suppression in discharge of volatile organic
compounds (Volatile Organic Compounds: VOC) has promoted use of
non-coated resins for housings used in the fields of electrical and
electronic equipment and OA equipment. For this reason, there has been a
desire for resins that have high designability that can address various
color tones, for example, can be colored in a vivid color or a deep
color. It has previously been reported that a transparent flame retardant
resin composition has high coloring physical properties and designability
in which a phosphoric acid ester-based flame retardant is compounded with
a rubber-reinforced styrene-based resin obtained by copolymerization of
an unsaturated carboxylic acid alkyl ester (for example, see Patent
Literatures 1 to 5). A transparent rubber-reinforced styrene-based resin
obtained by copolymerization of an unsaturated carboxylic acid alkyl
ester is used as a base resin, thus obtained transparent flame retardant
resin composition has high coloring properties and designability. Because
the unsaturated carboxylic acid alkyl ester is compounded, however,
stability of the flame retardancy and the mechanical properties,
particularly the falling dart impact resistance, weld strength, and
Charpy impact strength are insufficient, and further improvement thereof
has been desired. Moreover, a resin composition comprising a rubber
containing graft copolymer, a copolymer consisting of a monomer mixture
containing a methyl methacrylate monomer, and a flame retardant
compounded with these has been reported (for example, see Patent
Literature 6). The styrene-based resin disclosed in Patent Literature 6
demonstrates an effect in the flame retardancy, designability, and
scratch resistance, but stability of the flame retardancy and mechanical
properties, particularly the falling dart impact resistance, weld
strength, Charpy impact strength, and the like are inferior.
Additionally, the electrical and electronic equipment using this
styrene-based resin and the like do not show satisfactory results in a
product drop practical test. Accordingly, further improvement has been
desired. Meanwhile, a resin composition in which scratch resistance,
designability, and impact resistance are improved, and no flame retardant
is compounded has been reported (for example, see Patent Literature 7).
Unfortunately, the falling dart impact resistance, weld strength, and the
like of this resin composition do not show satisfactory results in the
product drop practical test, and therefore further improvement has been
desired.

[0010] An object of the present invention is to provide a styrene-based
resin composition which excels in flame retardancy, and at the same time
in falling dart impact resistance, weld strength, Charpy impact strength,
and color developability, and a resin molded article comprising the same.

Technical Solution

[0011] As a result of extensive research to solve the problems, the
present inventors have found out a material which can solve the problems,
and based on this knowledge, have completed the present invention.

[0012] Namely, the present inventors have completed a styrene-based resin
composition which excels in flame retardancy, and at the same time in
falling dart impact resistance, weld strength, Charpy impact strength,
and color developability by adding 5 to 20 parts by mass of a flame
retardant (D) to 100 parts by mass of a resin composition (1) comprising:
30 to 51% by mass of a graft copolymer (A) obtained by graft polymerizing
a diene-based rubbery polymer with an aromatic vinyl-based monomer and an
unsaturated nitrile monomer, 10 to 55% by mass of a copolymer (B)
comprising two or more of monomers selecting from the group consisting of
aromatic vinyl-based monomers, unsaturated nitrile monomers, and
unsaturated carboxylic acid alkyl ester monomers, and 15 to 39% by mass
of a copolymer (C) comprising one kind of unsaturated carboxylic acid
alkyl ester monomers, or two or more unsaturated carboxylic acid alkyl
ester monomers (wherein (A)+(B)+(C)=100% by mass), and further
controlling a proportion of the diene-based rubbery polymer to the resin
composition (1) to 15 to 25% by mass.

[0013] Namely, the present invention is as follows: [0014] [1] A
styrene-based resin composition comprising a resin composition (1) and 5
to 20 parts by mass of a flame retardant (D) based on 100 parts by mass
of the resin composition (1), wherein the resin composition (1)
comprising 30 to 51% by mass of a graft copolymer (A) obtained by graft
polymerizing a diene-based rubbery polymer with an aromatic vinyl-based
monomer and an unsaturated nitrile monomer, 10 to 55% by mass of a
copolymer (B) comprising two or more of monomers selecting from the group
consisting of aromatic vinyl-based monomers, unsaturated nitrile
monomers, and unsaturated carboxylic acid alkyl ester monomers, and 15 to
39% by mass of a copolymer (C) comprising one kind of unsaturated
carboxylic acid alkyl ester monomers, or two or more unsaturated
carboxylic acid alkyl ester monomers (wherein (A)+(B)+(C)=100% by mass),
and wherein a proportion of the diene-based rubbery polymer to the resin
composition (1) is 15 to 25% by mass. [0015] [2] The styrene-based resin
composition according to [1], wherein a falling dart impact 50%
destruction energy according to JIS K7211-1976 of a molded product
comprising said styrene-based resin composition and having a thickness of
2.5 mm is 4.0 J or more. [0016] [3] The styrene-based resin composition
according to [1] or [2], wherein a proportion of a unit component derived
from the aromatic vinyl-based monomer (As) in the components of the graft
copolymer (A) from which the diene-based rubbery components are excluded
is 60 to 90% by mass, a proportion of a unit component derived from the
aromatic vinyl-based monomer (Bs) in the copolymer (B) is 60 to 90% by
mass, and a difference (|As-Bs|) between the proportion of the unit
component derived from the aromatic vinyl-based monomer (As) and the
proportion of the unit component derived from the aromatic vinyl-based
monomer (Bs) is 0 to 5% by mass. [0017] [4] The styrene-based resin
composition according to any one of [1] to [3], wherein the component (C)
is a copolymer obtained by copolymerizing a methyl methacrylate monomer
and a methyl acrylate monomer. [0018] [5] The styrene-based resin
composition according to [4], wherein a proportion of the methyl acrylate
monomer contained in the copolymer (C) is 0.5 to 15% by mass. [0019] [6]
The styrene-based resin composition according to any one of [1] to [5],
wherein the resin composition (1) comprises 1 to 12% by mass of aromatic
polycarbonate (E), wherein (A)+(B)+(C)+(E)=100% by mass. [0020] [7] A
resin molded article comprising the styrene-based resin composition
according to any one of [1] to [6]. [0021] [8] The resin molded article
according to [7], wherein the resin molded article is molded at a metal
mold temperature of 60 to 90° C.

[0023] The graft copolymer (A) in the present invention is obtained by
graft polymerizing a diene-based rubbery polymer with an aromatic
vinyl-based monomer and an unsaturated nitrile monomer. Examples of the
diene-based rubbery polymer include conjugated diene-based rubbers such
as polybutadiene, butadiene-styrene copolymers, butadiene-acrylonitrile
copolymers, butadiene-acrylic copolymers, styrene-butadiene-styrene block
copolymers, polyisoprene, styrene-isoprene copolymers, and
styrene-isoprene-butadiene copolymers, and hydrogenated products thereof.
These can be used alone, or two or more thereof can be used in
combination. Among these, preferred diene-based rubbery polymers are
polybutadiene, polyisoprene, butadiene-styrene copolymers,
butadiene-acrylonitrile copolymers, and butadiene-acrylic copolymers, and
particularly preferred are polybutadiene, polyisoprene, butadiene-styrene
copolymers, styrene-isoprene copolymers, styrene-isoprene-butadiene
copolymers, butadiene-acrylonitrile copolymers, and butadiene-acrylic
copolymers. Use of these can provide a styrene-based resin composition
having high mechanical strength and color developability and resin molded
article thereof.

[0024] Examples of the aromatic vinyl-based monomer in the present
invention include styrene, α-methylstyrene, o-methylstyrene,
p-methylstyrene, ethylstyrene, p-t-butylstyrene, and vinylnaphthalene.
Among these, preferred aromatic vinyl-based monomers are styrene and
α-methylstyrene. These can be used alone, or two or more thereof
can be used in combination.

[0025] Examples of the unsaturated nitrile monomer in the present
invention include acrylonitrile, methacrylonitrile, and ethacrylonitrile.
Among these, preferred unsaturated nitrile monomer is acrylonitrile.
These can be used alone, or two or more thereof can be used in
combination.

[0026] The graft copolymer (A) can be obtained by graft polymerizing the
aromatic vinyl-based monomer, the unsaturated nitrile monomer, and other
monomer copolymerizable with the aromatic vinyl-based monomer.

[0027] The copolymer (B) can be obtained by copolymerizing the aromatic
vinyl-based monomer, the unsaturated nitrile monomer, and other monomer
copolymerizable with the aromatic vinyl-based monomer.

[0028] Examples of the other monomer include acrylic acid esters such as
methyl acrylate, ethyl acrylate, and butyl acrylate; similar substitution
products, methacrylic acid esters such; acrylic acids such as acrylic
acid and methacrylic acid; N-substituted maleimide-based monomers such as
N-phenylmaleimide and N-methylmaleimide; and glycidyl group containing
monomers such as glycidyl methacrylate. Among these, particularly
preferred are methyl acrylate, ethyl acrylate, butyl acrylate, methyl
methacrylate, N-phenylmaleimide, and glycidyl methacrylate.

[0029] However, in the case where the above-mentioned other monomer is
graft copolymerized with the graft copolymer (A), and in the case where
the above-mentioned other monomer is copolymerized with the copolymer
(B), the other monomer is used in the range in which the effects of the
present invention are not impaired. A preferred amount of the other
monomer is 0 to 40% by mass based on the graft copolymer (A) and based on
the copolymer (B), respectively.

[0030] In the present invention, from the viewpoint of the color
developability, the proportion of a unit component derived from the
aromatic vinyl-based monomer (As) in the components of the graft
copolymer (A) from which the diene-based rubbery polymer components are
excluded on the basis of calculation is preferably 60 to 90% by mass,
more preferably 70 to 85% by mass, and particularly preferably 75 to 85%
by mass. Moreover, from the viewpoint of the color developability, the
proportion of a unit component derived from the aromatic vinyl-based
monomer (Bs) in the copolymer (B) is preferably 60 to 90% by mass, more
preferably 75 to 85% by mass, and particularly preferably 77 to 83% by
mass. The difference (|As-Bs|) between the proportion of the unit
component derived from the aromatic vinyl-based monomer (As) and the
proportion of the unit component derived from the aromatic vinyl-based
monomer (Bs) is preferably 0 to 5% by mass, and more preferably 0 to 3%
by mass because a desired color tone is easier to obtain.

[0031] The proportion of the aromatic vinyl compound unit is detected by a
Fourier transform infrared spectrophotometer (hereinafter, abbreviated to
an FT-IR in some cases). As a sample for the FT-IR, a 0.01 to 0.08 μm
film produced by compression molding the graft copolymer (A), and a 0.01
to 0.08 μm film produced by compression molding the copolymer (B),
respectively.

[0032] As the FT-IR, an FT/IR-7000 made by JASCO Corporation is used. A
0.01 to 0.08 μm film produced by compression molding the copolymer
(B), for example, is used as the sample. The Bs is determined from the
absorbance (A1) at 2262 cm-1, the peak absorbance (A2) at 2238 to
2242 cm-1, the absorbance (A3) at 2222 cm-1, the absorbance
(E1) at 1792 cm-1, the peak absorbance (E2) at 1734 to 1738
cm-1, the absorbance (E3) at 1661 cm-1, the absorbance (S1) at
1617 cm-1, the peak absorbance (S2) at 1600 to 1606 cm-1, and
the absorbance (S3) at 1575 cm-1 by the following equation (I):

Bs=1.0/(A+E+1.0)×100 Equation (I) [0033] wherein
A=AA/SS×0.27599,

[0033] E=EE/SS×0.0438+0.005,

[0034] AA=A2-(A1-A3)×(wave number of A2-wave number of A3)/(wave
number of A1-wave number of A3)-A3,

[0035] SS=S2-(S1-S3)×(wave number of S2-wave number of S3)/(wave
number of S1-wave number of S3)-S3, and

[0036] EE=E2-(E1-E3)×(wave number of E2-wave number of E3)/(wave
number of E1-wave number of E3)-E3

[0037] A 0.01 to 0.08 μm film produced by compression molding the graft
copolymer (A), for example, is used as the sample. The As is determined
from A1, A2, A3, S1, S2, and S3 by the following equation (II):

As=1.0/(A+1.0)×100 Equation (II) [0038] wherein
A=AA/SS×0.27599,

[0039] AA=A2-(A1-A3)×(wave number of A2-wave number of A3)/(wave
number of A1-wave number of A3)-A3, and

[0040] SS=S2-(S1-S3)×(wave number of S2-wave number of S3)/(wave
number of S1-wave number of S3)-S3

[0041] The proportion of the aromatic vinyl compound unit is determined by
the Fourier transform infrared spectrophotometer (FT-IR) by an internal
standard method using a mathematical expression. In the internal standard
method, an internal standard substance having a predetermined
concentration is added together with a standard sample used for a
calibration curve. The ratio of the peak absorbance of the standard
sample to the peak absorbance of the internal standard substance is
taken. The relationship between the relative ratio and the concentration
of the standard sample is plotted as a calibration curve. The
coefficients "0.27599," "0.0438," "0.005," and the like are coefficients
determined by the internal standard method when the "FT/IR-7000 made by
JASCO Corporation" is used.

[0042] In the present invention, the volume average particle size of the
diene-based rubbery polymer in the graft copolymer (A) is preferably 0.1
to 1.2 μm, more preferably 0.15 to 0.8 μm, still more preferably
0.15 to 0.6 μm, and particularly preferably 0.2 to 0.4 μm from the
viewpoint of a balance among the mechanical strength, the fabricability,
and the appearance of the molded product.

[0043] The graft rate in the graft copolymer (A) is preferably adjusted
according to the refractive index of the mixture of the copolymer (B) and
the component (C). The graft rate is preferably 10 to 150% by mass, more
preferably 20 to 110% by mass, and still more preferably 25 to 60% by
mass from the viewpoint of the mechanical strength and the moldability.
The graft rate is defined as a mass proportion of monomers
graft-copolymerized to a rubbery polymer to the rubbery polymer. The
measurement method is as follows. A polymer produced by a polymerization
reaction is dissolved in acetone, and separated into components soluble
in acetone and components insoluble in acetone by a centrifuge. At this
time, the components soluble in acetone are components that do not
undergo a graft reaction in the copolymers subjected to the
polymerization reaction (non-grafted components), and the components
insoluble in acetone is the rubbery polymer and components grafted to the
rubbery polymer (grafted component). The value obtained by subtracting
the mass of the rubbery polymer from the weight of the components
insoluble in acetone is determined as the weight of the grafted
components. Accordingly, the graft rate can be determined from these
values.

[0044] The refractive index of the rubbery polymer is preferably 1.51 to
1.54 at 20° C. to be commensurate with the refractive index of the
mixture of the copolymer (B) and the component (C).

[0045] In the present invention, the proportion of the diene-based rubbery
polymer in the resin composition (1) is 15 to 25% by mass, and preferably
15 to 22% by mass. The proportion is more preferably 16 to 20% by mass.
If the proportion of the diene-based rubbery polymer is within the range,
the falling dart impact resistance and the color developability are
provided in a good balance.

[0046] The resin composition (1) in the present invention comprises the
graft copolymer (A), the copolymer (B), and the component (C), or
comprises the graft copolymer (A), the copolymer (B), the component (C),
and an aromatic polycarbonate (E).

[0047] The content of the graft copolymer (A) in the resin composition (1)
is 30 to 51% by mass, and preferably 35 to 45% by mass. If a content of
the graft copolymer (A) is within this range, a resin having a specific
content of a rubber is obtained in which the falling dart impact
resistance and the color developability are provided in a good balance.

[0048] The copolymer (B) in the present invention is obtained by
copolymerizing two or more selected from the group consisting of aromatic
vinyl-based monomers, unsaturated nitrile monomers, and unsaturated
carboxylic acid alkyl ester monomers. Examples of the unsaturated
carboxylic acid alkyl ester monomers include alkyl methacrylates such as
methyl methacrylate, cyclohexyl methacrylate, methylphenyl methacrylate,
and isopropyl methacrylate; and alkyl acrylates such as methyl acrylate,
ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate. Preferred are
methyl methacrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl
acrylate, and the like, and more preferred are butyl acrylate and methyl
methacrylate. Most preferred is n-butyl acrylate.

[0049] The content of the copolymer (B) in the resin composition (1) is 10
to 55% by mass, and preferably 15 to 50% by mass. If a content of the
copolymer (B) is within the range, a resin having high mechanical
strength is obtained.

[0050] The component (C) in the present invention is a copolymer
comprising one kind of unsaturated carboxylic acid alkyl ester monomers,
or two or more unsaturated carboxylic acid alkyl ester monomers. Examples
of the unsaturated carboxylic acid alkyl ester monomer include alkyl
methacrylates such as methyl methacrylate, cyclohexyl methacrylate,
methylphenyl methacrylate, and isopropyl methacrylate; and alkyl
acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, and
2-ethylhexyl acrylate. Among these, preferred are methyl methacrylate and
methyl acrylate.

[0051] In the case where the component (C) is a methyl methacrylate-methyl
acrylate copolymer, the content of the methyl acrylate monomers in the
copolymer is preferably 0.5 to 15% by mass, and more preferably 0.5 to
10% by mass from the viewpoint of the transparency.

[0052] The graft copolymer (A), the copolymer (B), and the component (C)
can be produced by a known method such as emulsion polymerization, bulk
polymerization, suspension polymerization, suspension bulk
polymerization, and solution polymerization.

[0053] The content of the component (C) in the resin composition (1) is 15
to 39% by mass, preferably 15 to 35% by mass, and more preferably 20 to
35% by mass. If a content of the component (C) is within this range,
stable color developability and flame retardancy are obtained. Moreover,
a resin having high falling dart impact resistance is obtained. The
related art also has reported a combination of the graft copolymer (A),
the copolymer (B), and the component (C). However, from the viewpoint of
placing importance on the color developability, only the compositions
containing the component (C) in a relatively large content existed, and
did not provide satisfactory color developability and flame retardancy in
the case that the component (C) was contained in a relatively small
content, although satisfactory color developability and flame retardancy
can be provided in the present application in which the component (C) is
contained in a relatively small content. In this application, the content
of the component (C) is thus reduced compared to that in the related art,
and a resin composition which excels in color developability, flame
retardancy, falling dart impact resistance, and Charpy impact strength
was successfully developed.

[0054] The flame retardant (D) in the present invention means a compound
that is liquid or solid at normal temperature, and can give flame
retardancy to a resin by addition of said compound. Examples thereof
include flame retardants such as phosphorus flame retardants such as
organic phosphorus compounds, red phosphorus, inorganic phosphoric acid
salts, halogen flame retardants, silica flame retardants, and silicone
flame retardants.

##STR00001## [0057] (wherein Ra, Rb, Rc, and Rd
each independently represent an aryl group, and one or more hydrogen
atoms may be substituted or not be substituted; n is a natural number, X
is an aromatic group derived from divalent phenols, and j, k, l, and m
are each independently 0 or 1.)

[0058] Among these, most preferred are condensed phosphoric acid ester
compounds represented by the general formula (2) below:

##STR00002##

[0059] Use of the flame retardant (D) represented by the formula (2) can
provide a composition having the flame retardancy, mechanical strength,
heat resistance, and designability in a particularly good balance.

[0060] Examples of red phosphorus include ordinary red phosphorus; red
phosphorus whose surface is in advance coated with a coating film of a
metal hydroxide selected from aluminum hydroxide, magnesium hydroxide,
zinc hydroxide, and titanium hydroxide; red phosphorus whose surface is
coated with a coating film formed of a metal hydroxide selected from
aluminum hydroxide, magnesium hydroxide, zinc hydroxide, and titanium
hydroxide and a thermosetting resin; and red phosphorus whose surface is
doubly coated with a coating film of a metal hydroxide selected from
aluminum hydroxide, magnesium hydroxide, zinc hydroxide, and titanium
hydroxide and with a coating film of a thermosetting resin formed
thereon.

[0063] These can be used alone, or two or more thereof can be used in
combination.

[0064] The amount of the flame retardant (D) to be added is 5 to 20 parts
by mass, and more preferably 10 to 20 parts by mass based on 100 parts by
mass of the resin composition (1). If the amount of the flame retardant
(D) to be added is within the range, a resin having stable flame
retardancy and high mechanical strength is obtained.

[0065] The styrene-based resin composition of the present invention
preferably attains a falling dart impact 50% destruction energy according
to JIS K7211-1976 of 4.0 J or more in a molded product article having a
thickness of 2.5 mm. From the viewpoint of evaluation of products, the
falling dart impact 50% destruction energy is more preferably 5.0 J or
more, and particularly preferably 5.9 J or more. A higher falling dart
impact 50% destruction energy is better considering the purpose of use of
the composition according to the present invention, but the falling dart
impact 50% destruction energy is preferably less than 10 J due to a
balance with other requirements. In order to attain the falling dart
impact 50% destruction energy of 4.0 J or more, the reduced viscosity
(ηsp/c) of the copolymer (B) is preferably 0.3 to 1.0 dl/g, more
preferably 0.35 to 1.0 dl/g, still more preferably 0.35 to 0.8 dl/g, and
particularly preferably 0.40 to 0.8 dl/g. Similarly, in order to attain
the falling dart impact 50% destruction energy of 4.0 J or more, the
reduced viscosity of the component (C) is preferably 0.18 to 0.8 dl/g,
more preferably 0.20 to 0.8 dl/g, still more preferably 0.25 to 0.80
dl/g, and particularly preferably 0.30 to 0.65 dl/g. The reduced
viscosity is obtained by measuring a flow time of a solution in a
Cannon-Fenske type capillary tube at 30° C., wherein the solution
being prepared by dissolving 0.50 g of the copolymer (B) or 0.50 g of the
component (C) in 100 ml of 2-butanone.

[0066] As a preferred method for molding the molded product having a
thickness of 2.5 mm, molding is performed at a setting temperature of
220° C. and a metal mold temperature of 60° C. by using an
injection molding machine. A preferred shape of the molded article is a
flat plate of 50 mm×90 mm×2.5 mm. The falling dart impact 50%
destruction energy is evaluated according to JIS K7211-1976. A ball type
2 (mass: 1±0.05 kg, shape: diameter of approximately 63 mm) is used as
a weight. The 50% destruction height is determined under an environment
of a temperature of 23° C. and a humidity of 50±5% using 20
test pieces, and converted to an energy.

[0067] Specifically, the calculation is performed from the equations (3)
and (4):

H50(50% destruction height)=H1+d[Σ(i×ni)/N±1/2]
(3), and

E50(50% destruction energy)=m×g×H50 (4). [0068]
Into the equations, H1: a test height (cm) at a height level (i) of
0,

[0069] d: a height interval (cm) when the test height is raised or
lowered,

[0070] i: a height level set to 0 at H1, and incremented or
decremented by 1,

[0071] ni: the number of test pieces broken (or not broken) at each level,

[0075] In the present invention, measurement and calculation were
performed at H1=60 cm, d=2.5 cm, and m=1 kg.

[0076] The styrene-based resin composition of the present invention has
high weld strength. The weld strength here is obtained as follows. Using
injection molding, molded products are produced by injecting the resin
from a single gate and two gates, respectively, into an ISO dumbbell
(thickness of 4 mm) The tensile strength of the obtained molded products
is evaluated according to ISO527-1. The weld strength is calculated from
two gates (tensile strength)/single gate (tensile strength)×100%.
The styrene-based resin composition according to the present invention
has a weld strength of 60% or more, preferably 80% or more.

[0077] As the aromatic polycarbonate (E), those produced by a known method
can be used. Specifically, usable are those produced by a known method
for reacting an aromatic dihydroxy compound with a carbonate precursor
such as an interface polymerization method in which an aromatic dihydroxy
compound is reacted with a carbonate precursor (for example, phosgene) in
the presence of a sodium hydroxide aqueous solution and a methylene
chloride solvent (for example, a phosgene method), and a
transesterification method (the melting method) in which an aromatic
dihydroxy compound is reacted with a carbonic diester (for example,
diphenyl carbonate), etc, and those produced by a method for solid phase
polymerizing a crystallized carbonate prepolymer obtained by the phosgene
method or the melting method (JP 1-158033 A, JP 1-271426 A, JP 3-68627 A,
and the like) can also be used.

[0078] The weight average molecular weight (Mw) of the aromatic
polycarbonate can be measured using gel permeation chromatography (GPC).
The measurement condition is as follows. Namely, tetrahydrofuran is used
as a solvent, and a polystyrene gel is used. The weight average molecular
weight (Mw) of the aromatic polycarbonate is determined using a molecular
weight calibration curve converted from a standard monodisperse
polystyrene constitution curve by the following equation:

Mpc=0.3591Mps1.0388 [0079] (wherein Mpc is the
molecular weight of aromatic polycarbonate, and Mps is the molecular
weight of polystyrene)

[0080] Two or more aromatic polycarbonates each having a different
molecular weight can be used in combination.

[0081] The content of the aromatic polycarbonate (E) in the resin
composition (1) is preferably 1 to 17% by mass, more preferably 1 to 12%
by mass, and particularly preferably 4 to 10% by mass. If a content of
the aromatic polycarbonate (E) is within this range, a resin having
stable flame retardancy and high color developability is obtained.

[0082] From the viewpoint of the flame retardancy and the transparency,
the content of the aromatic polycarbonate (E) preferably varies depending
on the weight average molecular weight Mw. For example, the relationship
between the weight average molecular weight Mw and the content G (% by
mass) preferably satisfies the following expressions (5) and (6). More
preferable is a range surrounded by trapezoids that satisfy the
expressions (5) and (7), and most preferable is a range surrounded by
trapezoids that satisfy the expressions (5) and (8).

13,000≦Mw≦30,000 (5)

1≦G≦-2.9×10-4×Mw+20.824 (6)

4≦G≦-2.9×10-4×Mw+20.824 (7)

4≦G≦-2.9×10-4×Mw+17.824 (8)

[0083] To the styrene-based resin composition of the present invention, a
colorant (F) can be added in order to give the designability. Examples of
the colorant (F) include inorganic pigments, organic pigments, metallic
pigments, and dyes. Examples of the inorganic pigments include titanium
oxide, carbon black, titanium yellow, iron oxide-based pigments,
ultramarine, cobalt blue, chromium oxide, spinel green, lead
chromate-based pigments, and cadmium-based pigments.

[0085] Examples of the metallic pigments include flake aluminum metallic
pigments, spherical aluminum pigments used to improve the weld
appearance, mica powder for pearl-like metallic pigments, and other
polyhedral particles of an inorganic substance such as glass coated with
a metal by plating or spattering.

[0087] These colorants can be used alone, or two or more thereof can be
used in combination.

[0088] Among these, a combination of three or more dyes is preferable. For
example, in the case where a jet-black tone is given, use of dyes of
three primary colors is preferred. Among these, a combination of a
perinone dye, a quinoline dye, and an anthraquinone dye is preferable.

[0089] The styrene-based resin composition of the present invention has
high color developability. The color developability here means an
excellent effect in which a desired color tone is easy to obtain in
coloring using the colorant (F). "Easy to obtain a desired color tone"
specifically means that it is easy to obtain L*, a*, and b* (measurement
according to JIS Z8729) for a target color tone, and no great difference
in the color tone is apparently found. For example, in the case where a
blacker color tone is desired, it is desired that L* is smaller. Usually,
in the case where the jet-blackness is demanded, L* is preferably 11 or
less, and more preferably 9 or less. In the case where a high whiteness
is desired, it is desired that L* is larger. In the case where standard
pure white is demanded, L* is preferably 90 or more, and more preferably
95 or more. As the resin having such high color developability, preferred
are resins that can use a wider range of the colorant, and has a high
total light transmittance in a natural color of the resin.

[0090] As a method for mixing the styrene-based resin composition
according to the present invention, a known melt mixing method can be
used. Specifically, examples thereof include batch type kneading machines
such as a mixing roll, a Banbury mixer, and a pressure kneader; and
continuous kneading machines such as a single screw extruder and a twin
screw extruder.

[0091] Examples of the order of kneading include a method for kneading the
total amount in batch, or a method for producing a masterbatch containing
the flame retardant (D) or the aromatic polycarbonate (E) in a high
concentration, and subsequently diluting the masterbatch. Preferred are a
batch kneading method in which only the flame retardant (D) is separately
fed, and a method for producing a masterbatch in which a combination of
the copolymer (B) and the component (C) or a combination of the copolymer
(B), the component (C), and the aromatic polycarbonate (E) is kneaded in
advance, and subsequently the graft copolymer (A) and the flame retardant
(D) are added. By these methods, a composition which excels in flame
retardancy, mechanical strength, and transparency can be obtained.

[0092] The resin molded article according to the present invention is
obtained by a known method usually used for molding thermoplastic resins
such as injection molding, injection compression molding, extrusion
molding, blow molding, inflation molding, vacuum molding, and press
molding methods. Among these, injection molding and injection compression
molding are preferable. Heat cycle molding in which a metal mold
temperature is raised and cooled in a short time in the injection molding
is most preferable.

[0093] In the injection molding, from the viewpoint of transferability to
the surface of the cavity, molding is performed by adjusting the metal
mold temperature at preferably 50 to 90° C., and more preferably
60 to 90° C. If the cavity surface temperature is high, the time
to cool is longer. Accordingly, use of the heat cycle molding method for
heating and cooling the cavity surface in a short time is preferred.

[0095] Moreover, in order to give the designability, a known colorant such
as inorganic pigments, organic pigments, metallic pigments, and dyes can
be added.

EXAMPLES

[0096] Examples and Comparative Examples below are for more specifically
describing the present invention.

[0097] Evaluation and measurement in Examples were performed according to
the following methods.

(1) Notched Charpy Impact Strength (kJ/m2)

[0098] The notched Charpy impact strength was evaluated according to
ISO179.

(2) Flexural Modulus (MPa)

[0099] The flexural modulus was evaluated according to ISO178.

(3) Weld Strength

[0100] Using injection molding, molded products were produced by injecting
the resin from a single gate and two gates into an ISO dumbbell
(thickness of 4 mm). The tensile strength of the obtained molded products
was evaluated according to ISO527-1. The weld strength was calculated
from two gates (tensile strength)/single gate (tensile
strength)×100%.

[0101] If the weld strength was less than 60%, it was considered fail
(×). If the weld strength was 60% or more and less than 80%, it was
considered fair (Δ). If the weld strength was 80% or more, it was
considered good (◯).

(4) Falling Dart Impact Resistance (J)

[0102] Using an injection molding machine, a flat plate measuring 5
cm×9 cm and having a thickness of 2.5 mm was produced at a cylinder
temperature of 220° C. and a metal mold temperature of 60°
C. The 50% destruction energy was evaluated according to JIS K7211-1976.

[0103] If it was less than 4.0 J, it was considered fail (×). If it
was 4.0 J or more, it was considered good (◯).

(5) Color Developability

[0104] Using an injection molding machine, a flat plate measuring 5
cm×9 cm and having a thickness of 2.5 mm was produced at a cylinder
temperature of 220° C. and a metal mold temperature of 60°
C. L* was measured according to JIS Z8729, and jet-blackness was
evaluated.

[0105] If L* was more than 11, it was considered fail (×). If L* was
more 9 and 11 or less, it was considered fair (Δ). If L* was 9 or
less, it was considered good (◯).

(6) Flame Retardancy

[0106] The flame retardancy was evaluated according to UL-94. (thickness
of 1.6 mm) Absolutely dry condition: a test piece was treated at
70° C. for 168 hours, and cooled for 4 hours or more in a
desiccator including silica gel, and a burning test was performed.

[0107] Wet condition: a test piece was left under an atmosphere of
23° C. and 50% humidity for 30 days, and a burning test was
performed.

[0108] If the test piece passed the tests both in the absolutely dry
condition and the wet condition, it was considered good (◯).
If the test piece did not pass the test in any one of the absolutely dry
condition and the wet condition, it was considered fail (×).

[0109] The copolymer (B) was formed into a film of 0.01 to 0.08 μm by
compression molding. Using an FT/IR-7000 made by JASCO Corporation, the
absorbance (A1) at 2262 cm-1, the peak absorbance (A2) at 2238 to
2242 cm-1, the absorbance (A3) at 2222 cm-1, the absorbance
(E1) at 1792 cm-1, the peak absorbance (E2) at 1734 to 1738
cm-1, the absorbance (E3) at 1661 cm-1, the absorbance (S1) at
1617 cm-1, the peak absorbance (S2) at 1600 to 1606 cm-1, and
the absorbance (S3) at 1575 cm-1 were detected, and the proportion
(Bs) was determined by the following equation (I):

Bs=1.0/(A+E+1.0)×100 Equation (I), [0110] wherein
A=AA/SS×0.27599

[0110] E=EE/SS×0.0438+0.005

[0111] AA=A2-(A1-A3)×(wave number of A2-wave number of A3)/(wave
number of A1-wave number of A3)-A3

[0112] SS=S2-(S1-S3)×(wave number of S2-wave number of S3)/(wave
number of S1-wave number of S3)-S3

[0113] EE=E2-(E1-E3)×(wave number of E2-wave number of E3)/(wave
number of E1-wave number of E3)-E3

[0114] The graft copolymer (A) was formed into a film of 0.01 to 0.08
μm by compression molding. Using an FT/IR-7000 made by JASCO
Corporation, A1, A2, A3, S1, S2, and S3 were detected, and the proportion
(As) was determined by the following expression (II):

As=1.0/(A+1.0)×100 Equation (II), [0115] wherein
A=AA/SS×0.27599

[0116] AA=A2-(A1-A3)×(wave number of A2-wave number of A3)/(wave
number of A1-wave number of A3)-A3

[0117] SS=S2-(S1-S3)×(wave number of S2-wave number of S3)/(wave
number of S1-wave number of S3)-S3

(Graft Copolymer A)

<Production of Diene-Based Rubbery Polymer>

[0118] <Production of Polybutadiene Rubber Latex>

[0119] Nine hundred and fifty parts by mass of a butadiene monomer, 50
parts by mass of acrylonitrile, 135 parts by mass of deionized water
(concentration of iron: less than 0.02 ppm), 3.0 parts by mass of
potassium oleate, 0.3 parts by mass of potassium persulfate, 0.2 parts by
mass of tertiary dodecyl mercaptan, and 0.18 parts by mass of potassium
hydroxide were placed in a pressure-resistant container with a stirrer.
The temperature was raised to 70° C., and polymerization was
started. The polymerization was performed for 15 hours to obtain a
polybutadiene latex having a volume average particle size of 80 nm
measured by a Microtrack particle size analyzer "nanotrac 150" (trade
name) made by NIKKISO CO., LTD. and a solid content of 40% by mass.

[0120] To this obtained polybutadien latex, 0.1 parts by mass of an
emulsifier:

##STR00003## [0121] was added based on 100 parts by mass of the solid
content in the latex, and the latex was stirred for 5 minutes. Then, 0.65
parts by mass of acetic acid was added. Subsequently, 0.65 parts by mass
of potassium hydroxide was added to obtain a stable latex. The latex was
a latex having particle size distribution with the volume average
particle size of 250 nm without forming a coagulum, and was an aggregated
latex having a high concentration of the solid content of 37% by mass.
The mass distribution rate of the latex having a particle size of 350 nm
or more was 11% by mass.

<Production of Graft Copolymer (A-1)>

[0122] To 135 parts by mass of the polybutadiene rubber latex produced
above, 0.1 parts by mass of tertiary dodecyl mercaptan and 15 parts by
mass of deionized water (the concentration of iron: less than 0.02 ppm)
were added, a gaseous phase was replaced by nitrogen, then an aqueous
solution prepared by dissolving 0.06 parts by mass of sodium formaldehyde
sulfoxylate, 0.0008 parts by mass of ferrous sulfate, and 0.02 parts by
mass of ethylenediaminetetraacetic acid disodium salt in 25 parts by mass
of deionized water was added, and the temperature was raised to
55° C. Subsequently, while the temperature was raised over 1.5
hours to 70° C., a monomer mixed solution consisting of 10 parts
by mass of acrylonitrile, 40 parts by mass of styrene, 0.4 parts by mass
of tertiary dodecyl mercaptan, and 0.15 parts by mass of cumene
hydroperoxide, and an aqueous solution prepared by dissolving 0.035 parts
by mass of sodium formaldehyde sulfoxylate in 25 parts by mass of
deionized water were added over 4 hours. After the addition was
completed, 0.02 parts by mass of cumene hydroperoxide was added. While
the reaction tank was controlled at 70° C. for another 1 hour, the
polymerization reaction was completed.

[0123] A silicone resin antifoaming agent and a phenol-based antioxidant
emulsion were added to the thus-obtained ABS latex, and deionized water
was added thereto and adjusted so that the concentration of the solid
content was 10% by mass. The latex was heated to 70° C., and an
aluminium sulfate aqueous solution was added thereto to solidify the
latex. The obtained product was subjected to solid liquid separation by a
screw press. The moisture content at this time was 10% by mass. The
obtained product was dried to obtain Graft Copolymer (A-1).

[0124] The Graft Copolymer (A-1) consisted of 10% by mass of
acrylonitrile, 50% by mass of butadiene, and 40% by mass of styrene,
wherein the graft rate was 46% by mass, the reduced viscosity of the
non-grafted components (a content soluble in acetone) (0.50 g/100 ml, in
the 2-butanone solution, measured at 30° C.) was 0.31 dl/g.

<Production of Graft Copolymer (A-2)>

[0125] By the same method as that in the case of Production of Copolymer
(A-1), Graft Copolymer (A-2) consisting of 12.5% by mass of
acrylonitrile, 50% by mass of butadiene, and 37.5% by mass of styrene was
obtained. This Graft Copolymer (A-2) has the graft rate of 46% by mass,
and the reduced viscosity of the non-grafted components (a content
soluble in acetone) (0.50 g/100 ml, in the 2-butanone solution, measured
at 30° C.) of 0.33 dl/g.

<Production of Styrene Butadiene Rubber Latex>

[0126] Nine hundred and fifty parts by mass of a butadiene monomer, 50
parts by mass of styrene, 135 parts by mass of deionized water (the
concentration of iron: less than 0.02 ppm), 3.0 parts by mass of
potassium oleate, 0.3 parts by mass of potassium persulfate, 0.2 parts by
mass of tertiary dodecyl mercaptan, and 0.18 parts by mass of potassium
hydroxide were placed in a pressure-resistant container with a stirrer.
The temperature was raised to 60° C., and polymerization was
started. The polymerization was performed for 15 hours to obtain a
styrene butadiene rubber latex having a volume average particle size of
80 nm measured by a Microtrack particle size analyzer "nanotrac 150"
(trade name) made by NIKKISO CO., LTD. and a solid content of 40% by
mass.

[0127] To this obtained styrene butadiene rubber latex, 0.1 parts by mass
of an emulsifier represented by the formula (9) was added based on 100
parts by mass of the solid content in the latex, and the obtained mixture
was stirred for 5 minutes. Then, 0.65 parts by mass of acetic acid was
added. Subsequently, 0.65 parts by mass of potassium hydroxide was added
to obtain a stable latex. The latex was a latex having particle size
distribution with the volume average particle size of 250 nm without
forming a coagulum, and was a condensed styrene butadiene rubber latex
having a high concentration of the solid content of 37% by mass. The mass
distribution rate of the latex having a particle size of 350 nm or more
was 11% by mass.

<Production of Graft Copolymer (A-3)>

[0128] To 135 parts by mass of the styrene butadiene rubber latex produced
above, 0.1 parts by mass of tertiary dodecyl mercaptan and 15 parts by
mass of deionized water (the concentration of iron: less than 0.02 ppm)
were added, a gaseous phase was replaced by nitrogen, then an aqueous
solution prepared by dissolving 0.06 parts by mass of sodium formaldehyde
sulfoxylate, 0.0008 parts by mass of ferrous sulfate, 0.02 parts by mass
of ethylenediaminetetraacetic acid disodium salt in 25 parts by mass of
deionized water was added thereto, and the temperature was raised to
55° C. Subsequently, while the temperature was raised over 1.5
hours to 70° C., a monomer mixed solution consisting of 10 parts
by mass of acrylonitrile, 40 parts by mass of styrene, 0.4 parts by mass
of tertiary dodecyl mercaptan, and 0.15 parts by mass of cumene
hydroperoxide, and an aqueous solution prepared by dissolving 0.035 parts
by mass of sodium formaldehyde sulfoxylate in 25 parts by mass of
deionized water were added over 4 hours. After the addition was
completed, 0.02 parts by mass of cumene hydroperoxide was added. While
the reaction tank was controlled at 70° C. for another 1 hour, the
polymerization reaction was completed.

[0129] A silicone resin antifoaming agent and a phenol-based antioxidant
emulsion were added to the thus-obtained ABS latex, and deionized water
was added thereto and adjusted so that the concentration of the solid
content was 10% by mass. The latex was heated to 70° C., and an
aluminium sulfate aqueous solution was added to solidify the latex. The
obtained product was subjected to solid liquid separation by a screw
press. The moisture content at this time was 10% by mass. The obtained
product was dried to obtain Graft Copolymer (A-3).

[0130] The Graft Copolymer (A-3) consisted of 10% by mass of
acrylonitrile, 50% by mass of butadiene, and 40% by mass of styrene,
wherein the graft rate was 46% by mass, the reduced viscosity of the
non-grafted components (a content soluble in acetone) (0.50 g/100 ml, in
the 2-butanone solution, measured at 30° C.) was 0.31 dl/g.

(Copolymer B)

<Production of Copolymer (B-1)>

[0131] According to the method in Example 1 described in Japanese Patent
No. 1960531, a mixed solution of acrylonitrile and styrene, and secondary
butyl alcohol as a solvent was prepared, and continuously added to a
polymerization reactor. The temperature of the reactor was controlled
from 140 to 160° C. to make a polymerization reaction.

[0132] Subsequently, the non-reacted monomer was removed under vacuum to
obtain solid powder of Copolymer (B-1). Copolymer (B-1) consisted of 20%
by mass of acrylonitrile and 80% by mass of styrene, wherein the reduced
viscosity was 0.75 dl/g.

<Production of Copolymer (B-2)>

[0133] By the same method as that in the case of Copolymer (B-1),
Copolymer (B-2) was obtained. Copolymer (B-2) consisted of 25% by mass of
acrylonitrile and 75% by mass of styrene, wherein the reduced viscosity
was 0.75 dl/g.

<Production of Copolymer (B-3)>

[0134] By the same method as that in the case of Copolymer (B-1),
Copolymer (B-3) was obtained. Copolymer (B-3) consisted of 30% by mass of
acrylonitrile and 70% by mass of styrene, wherein the reduced viscosity
was 0.67 dl/g.

(Copolymer C)

<Production of Copolymer (C-1)>

[0135] To a monomer mixture comprising 68.6 parts by mass of methyl
methacrylate, 1.4 parts by mass of methyl acrylate and 30 parts by mass
of ethylbenzene, 0.015 parts by mass of
1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane and 0.15 parts by mass of
n-octylmercaptan were added and uniformly mixed. The solution was
continuously fed to an airtight pressure-resistant reactor having an
inner volume of 10 L, and polymerized under stirring at an average
temperature of 135° C. for an average residence time of 2 hours.
The obtained product was continuously fed to a storage tank connected to
the reactor, and introduced to a volatile content removing apparatus kept
at 260° C. and a high vacuum of 10 mmHg to devolatilize and
recover the non-reacted monomer and the solvent, and further continuously
transferred to an extruder in a molten state. Here, lauric acid and
stearyl alcohol were quantitatively fed at 90° C. in a molten
state from an additive inlet port connected to the extruder to obtain
pellets of Copolymer (C-1). The reduced viscosity of the obtained
copolymer was 0.35 dl/g. The composition was analyzed using a proton NMR
method, and a result that methyl methacrylate unit/methyl acrylate
unit=98.0/2.0 (mass ratio) was obtained. Further, the amounts of lauric
acid and stearyl alcohol in the resin composition were determined, and
found out that the amount of lauric acid was 0.03 parts by mass and that
of stearyl alcohol was 0.1 parts by mass based on 100 parts by mass of
the resin composition.

<Production of Copolymer (C-2))>

[0136] By the same method as that in the case of production of Copolymer
(C-1), Copolymer (C-2) was obtained wherein methyl methacrylate
unit/methyl acrylate unit=86.5/13.5 (weight ratio), and the reduced
viscosity was 0.32 dl/g.

[0140] Aromatic Polycarbonate (E-1) was a bisphenol A-based polycarbonate
produced from bisphenol A and diphenyl carbonate by melt
transesterification, and contained 400 ppm of
octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate as a hindered
phenol-based antioxidant and 200 ppm of tris(2,4-di-t-butylphenyl)
phosphite as a phosphite-based heat stabilizer.

[0141] The weight average molecular weight (Mw)=15,000, and [0142] the
phenolic terminal group ratio (proportion of the phenolic terminal group
to the number of the total terminal groups)=29 mol %.

<Production of Aromatic Polycarbonate (E-2)>

[0143] By the same method as that in the case of Aromatic Polycarbonate
(E-1), Aromatic Polycarbonate (E-2) was obtained. The weight average
molecular weight (Mw) was 26,000, and the phenolic terminal group ratio
was 25 mol %.

[0148] The compounding composition in Table 1 sufficiently dried to remove
moisture was mixed, then put into a hopper. While the flame retardant (F)
was quantitatively put into the hopper using a quantitative feeder, the
compounding composition was kneaded using a twin screw extruder (PCM-30,
L/D=28, made by Ikegai Corp.) on the condition of a cylinder setting
temperature of 260° C., the number of rotation of the screw of 200
rpm, and a discharge rate of the kneaded resin of 12 kg/hr to obtain
resin pellets, and the respective properties were evaluated. The result
of evaluation is shown in Table 1.

[0149] As shown in Table 1, in the case where the conditions defined in
the present invention are not satisfied, the effects of the present
invention cannot be obtained. In contrast, in the styrene-based resin
composition of the present invention, it turns out that excellent effects
are obtained in the flame retardancy, falling dart impact resistance,
weld strength, Charpy impact strength, color developability, and
mechanical properties.